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Keywords:

  • diagnosis;
  • pervasive developmental disorders (PDD);
  • reliability;
  • semistructured interview;
  • validity

Abstract

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

Aim:  To test the reliability and validity of the Pervasive Developmental Disorders Assessment System (PDDAS), a Japanese semistructured interview system.

Methods:  The PDDAS, consisting of 91 items including 12 major items corresponding to 12 items in criterion A of DSM-IV autistic disorder criteria, 36 items on autistic symptoms and three Asperger's disorder (AS) screening items for diagnosing pervasive developmental disorders (PDD) and their subtypes and 40 items for other information including early development and past/family histories, was administered to mothers of 77 PDD children and 64 non-PDD children.

Results:  The PDDAS had satisfactory interrater reliability (ranges of κ, r and raw agreement rate were 0.69–1.00 in 76 items, 1.00 in 11 items and 0.91–1.00 in four κ un-calculable items, respectively). Thirty-three of the 36 items and all of the 12 major items scored significantly higher in the PDD than non-PDD groups to show satisfactory discriminant validity. PDDAS and consensus DSM-IV diagnoses agreed in the 77 children in PDD diagnosis and disagreed in only two children in subtype diagnoses of autistic disorder and PDD not otherwise specified.

Conclusions:  The PDDAS, which takes 1.5 h to administer, seems to have clinical and research utility, although further investigation is necessary.

SINCE THE PUBLICATION of the World Health Organization's ICD-101 and American Psychiatric Association's DSM-IV,2 these diagnostic criteria for subtypes of pervasive developmental disorders (PDD) have been standard criteria worldwide. In both systems, diagnostic criteria for childhood autism/autistic disorder are a key component on which diagnostic criteria for other PDD subtypes are based. But with such criteria diagnostic problems are not rare, even in childhood autism/autistic disorder. This is because those criteria do not specify the age range of subjects wherein the criteria are applied and do not rate symptom severity despite the facts that autistic symptoms usually become less intense after infancy and no evaluation of symptom severity could result in over-diagnosing childhood autism/autistic disorder. To overcome such problems and standardize the diagnostic procedure of childhood autism, the Autism Diagnostic Interview (ADI)3 and its revision (ADI-R),4,5 semistructured interviews based on ICD-10 diagnostic criteria for childhood autism, were developed mainly for research in English-speaking countries. But the ADI-R is not readily available in non-English speaking countries and is not designed to diagnose PDD subtypes other than childhood autism. In addition, ICD-10/DSM-IV criteria for childhood autism/autistic disorder involve items that need interpretation in the context of a culture in which the subjects of diagnosis live. For example, ‘impairment in using facial expression and gesture to regulate social interaction’ in the first item for abnormality in social interaction in ICD-10/DSM-IV criteria for childhood autism/autistic disorder is difficult to apply to Japanese subjects, who do not use such maneuvers so much as Western people.

Because the prevalence of PDD is now believed to be approximately 1%6 and early diagnosis and intervention are important to support development of PDD infants, we created the Pervasive Developmental Disorders Assessment System (PDDAS) to help Japanese professionals diagnose PDD subtypes in a standardized way according to DSM-IV. The objective of the present study was to test the reliability and validity of the PDDAS in children with and without PDD.

METHODS

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

Instrument

The PDDAS, a 62-page Japanese document, is a semistructured diagnostic interview system consisting of 91 items divided into 16 sections to gather information on the development and symptoms of a possible PDD subject from his/her mother, in order to diagnose PDD and its subtypes according to DSM-IV.

Of the 91 items, 40 items in sections I–XI, XIII, XV and XVI and the rating system are shown in the left column in Table 1. Sections I–VII concern early development. Sections VIII–X examine developmental regression.7 Section XI concerns developmental abnormalities before age 3 in three areas (abnormality at least in one of them is needed to diagnose autistic disorder) in criterion B of DSM-IV criteria for autistic disorder (AD), and section XIII verifies atypicality in age at onset (i.e. all abnormalities in section XI emerging after age 3). Sections XV and XVI evaluate family and past histories.

Table 1.  Interrater reliability (κ or r) of 40 items in 14 sections of PDDAS
Sections I–XI, XIII, XV and XVI and abbreviated itemsnGrade/valueκ/r
  • *

    < 0.01.

  • In 17 items the number of children is smaller than 141 because the items did not apply to some children.

  • §

    Raw agreement rate because κ was uncalculable. r, Pearson's correlation coefficient.

  • +, present; ±, somewhat; −, absent. PDDAS, Pervasive Developmental Disorders Assessment System.

I. Babyhood (by age 1):
 Responsiveness1410+; 1±; 2−0.92*
 Separation anxiety1410+; 1±; 2−1.00*
 Stranger anxiety1410+; 1±; 2−1.00*
II. Age at first walking140Months1.00*
III. Hyperactivity in infancy1400−; 1±; 2+1.00*
 If any, it was prominent from ages A to B83A: months1.00*
83B: months1.00*
IV. Age at first word136Months1.00*
V. Age at first phrase113Months1.00*
VI. Pointing by finger:
 a. See a parent while pointing to an object of interest1400+; 1±; 2−0.93*
 Age at first such pointing120Months1.00*
 b. See a parent while pointing to an object for request1400+; 1±; 2−1.00*
 Age at first such pointing105Months1.00*
 c. See a parent while pointing to a picture in a book1410+; 1±; 2−0.93*
 Age at first such pointing117Months1.00*
 d. Point to an object by a hand1410−; 1+1.00*
 Age at first such behavior26Months1.00*
VII. Age at first successful removal of a diaper70Months1.00*
VIII. Rett's disorder in DSM-IV141No Yes1.00*
IX. Speech regression:141No Yes1.00*
 If any, its age at onset10Months1.00*
 a. Speech level before regression: 1. single word; 2. phrase111. 2.1.00§
 b. Development before regression: 1. abnormal; 2. normal111. 2.0.91§
 c. Precipitating factor111−; 2+1.00*
X. Childhood disintegrative disorder in DSM-IV141No Yes1.00§
XI. Developmental abnormality before age 3:
 No, ‘No’ in all of below (1–3); Yes, otherwise141No Yes0.88*
 1 Social interaction disturbance:
 1 Interest in children1410+; 1±; 2−0.92*
 2 Attachment to mother1410+; 1±; 2−0.91*
 3 Response to name calling1410+; 1±; 2−0.93*
 No, + in all of above (1–3); Yes, otherwise141No Yes0.88*
 2 Communication disturbance:1410−; 1±; 2+0.81*
 No, − in above rating; Yes, otherwise141No Yes0.83*
 3 Symbolic/imaginative play:1410+; 1±; 2−0.93*
 No (unimpaired), + in above rating; Yes, otherwise141No Yes0.93*
XIII. Ages at onset of all abnormalities in XI after age 3141No Yes1.00§
XV. Family history in 1st and 2nd degree relatives:
 a. Developmental disorders1410−; 1+1.00*
 b. Mood disorders1410−; 1+0.99*
 c. Other mental disorders1410−; 1+0.98*
XVI. Past history:
 a. Convulsion/loss of consciousness1410−; 1+1.00*
 b. Other medical problems1410−; 1+1.00*

As shown in the left column in Table 2, section XII involves three areas (1, social interaction impairment; 2, communication impairment; and 3, restricted/stereotyped interests/behavior), 12 major items divided into the three areas each of which has four major items (a–d), and 36 items on autistic symptoms (abbreviated in English to help non-Japanese readers know their contents, because the PDDAS has no English version, see Appendix I for a sample) divided into the 12 major items each of which has 2–4 items. We created each of the 36 items, the key structure of the PDDAS, to embody the concept of a major item, to which it belongs, in clinician-friendly Japanese terms derived from the literature and our clinical experiences to ensure their content validity. The three areas and 12 major items, described in Japanese terms used in everyday clinical settings, correspond to the three areas and 12 items in criterion A of DSM-IV criteria for AD (refer to DSM-IV2 and its Japanese translation8 for original English and Japanese expressions). After area 1, three Asperger's disorder (AS) screening items exist.

Table 2.  Interrater reliability (κ) and discriminant validity (mean difference) of items in section XII of PDDAS at lifetime rating when symptoms were most prominent before age 4
Areas 1–3, major items (a–d) and items (a–d) (abbreviated)nκMean scorez (U-test)
PDDNon-PDD
  • *

    < 0.01.

  • In four major items and 16 items, the number of children is smaller than 141 because the items did not apply to some children.

  • Mean major item score was calculated by assigning 0, 1 and 2 for N, S and D, respectively.

  • n.s., not significant; PDDAS, Pervasive Developmental Disorders Assessment System.

(1) Social interaction impairment
(a) Lack of non-verbal behaviors (D, n of 2 > 0)1410.94*1.050.068.47*
(a) Lack of eye contact1410.91*0.970.067.84*
(b) Poor facial expression1410.91*0.480.005.46*
(b) Poor peer relationship (D, n of 2 > 1)610.69*1.160.125.64*
(a) Poor social interaction with other children610.78*1.210.125.68*
(b) Poor imaginative play with other children610.70*0.950.025.64*
(c) Inability to play a game460.72*1.070.193.52*
(c) Lack of sharing enjoinment (D, n of 2 > 1)1410.95*1.210.118.03*
(a) Lack of showing objects of interest to others1410.91*1.170.117.46*
(b) Lack of showing achievements to others1410.97*1.140.037.88*
(c) Lack of asking others to play with1410.87*0.830.096.27*
(d) Dislike of others joining in his/her play1410.99*0.900.226.01*
(d) Lack of emotional reciprocity (D, n of 2 > 1)1410.92*1.250.089.63*
(a) Lack of interest in others1410.81*1.130.148.82*
(b) Lack of empathy to others1410.88*1.080.029.18*
(c) Lack of comforting others1120.82*1.290.187.25*
(d) Inappropriate emotional responses1410.80*0.740.094.85*
AS screening items:
1. No speech delay: No Yes1361.00*   
2. No mental development delay: No Yes1340.91*   
3. AS diagnosis (no other disorder): No Yes1411.00*   
(2) Communication impairment
(a) Speech development delay (D, n of 2 > 1)1410.87*1.390.556.39*
(a) Delay in or lack of speech development1410.83*1.360.804.03*
(b) Lack of facial expression or gesture1400.86*0.890.086.71*
(c) Lack of pointing by finger to request things1410.76*1.040.275.33*
(d) Takes other person's hand to use it to do things1410.94*1.080.424.45*
(b) Inability to converse (D, n of 2 > 0)470.72*1.300.054.76*
(a) Fluent but one-way traffic speaking470.69*1.200.035.05*
(b) Dislike of talking about uninterested topics470.69*1.300.035.07*
(c) Stereotyped language (D, n of 2 > 2)1140.92*1.080.336.70*
(a) Stereotypic utterances or echolalia1160.93*1.510.346.56*
(b) Neologism/idiosyncratic use of a word1140.92*0.320.07n.s.
(c) Pronominal reversal950.92*1.360.634.69*
(d) Inappropriate questioning790.86*1.240.225.37*
(d) Lack of imaginative plays (D, n of 2 > 1)1110.79*0.750.175.11*
(a) Lack of imitative behavior1260.81*0.420.063.61*
(b) Lack of make-believe play1110.77*0.760.085.61*
(c) Lack of play of acting like others580.84*1.060.43n.s.
(3) Restricted/stereotyped interests/behavior
(a) Restricted interests (D, n of 2 > 0)1410.88*1.740.845.64*
(a) Adherence to objects other than toys1410.91*1.520.725.33*
(b) Adherence to a toy or something like that1410.84*1.260.594.31*
(c) Adherence to the movement of objects1410.85*0.940.145.79*
(b) Adherence to routines (D, n of 2 > 0)1410.87*1.750.916.40*
(a) Resistance to change1410.86*1.210.445.09*
(b) Other adherences1410.83*1.680.736.66*
(c) Stereotyped behaviors (D, n of 2 > 0)1410.86*1.180.285.91*
(a) Spinning, jumping, rocking1410.92*1.170.425.52*
(b) Hand flapping, finger mannerism1410.93*0.480.004.86*
(c) Seeing objects edgewise/from close distance1410.87*0.750.174.96*
(d) Absorption in parts of objects (D, n of 2 > 0)1410.86*0.700.094.79*
(a) Prefers part of an object to its whole1410.91*0.660.094.53*
(b) Prefers texture, smell of an object to its whole1410.74*0.100.00n.s.

Each of the 36 items receives lifetime rating (before age 4 when autistic symptoms are usually most prominent) and present rating (average status of the symptom for the recent month) on a 3-point scale (0, not applied; 1, slightly applied; 2, definitely applied). Each major item is rated D (the AD diagnostic item represented by it is ‘definitely applied’ to the subject), if the number of its items that scored 2, meets the criterion in parentheses in the left column of Table 2, for example (D, n of 2 > 1) means that the major item is rated D if the number (n) of its rated items that scored 2 is ≥2); or S (slightly applied), if it is not rated D but has at least one item that scored 2 or at least half of its rated items scored 1; or N (not applied), if it is not rated D nor S. We set the criteria for D in each major item and the criteria for S shared by all major items by examining results of clinical application of the 36 items to more than 50 PDD patients before starting this study.

Some major items and items are not rated depending on the age or development of a subject. In area 1, the major item (b) is not rated in a child with a developmental age estimated to be lower than 3 years, and item (c) in the major item (d) is not rated in a child with a developmental age estimated to be lower than 2 years. In area 2, items (a) and (b) in the major item (a) are not rated in a child under chronological age 2 and item (c) in the major item (a) is not rated in a child under chronological age 1.5; the major item (b) is not rated in a child who cannot express requests well in words; the major item (c) is not rated in a child with no speech; and items (a) and (b) in the major item (d) are not rated in a child with a developmental age estimated to be under 2 years, and item (c) in the major item (d) is not rated in a child with a developmental age estimated to be under 3 years. Other items wherein a rater feels that it is not possible to rate the child are also not rated. If more than half of items under a major item are not rated, the major item is not rated.

The short version of the PDDAS (PDDAS-SV), a 4-page Japanese document, involving the 16 sections and all of the 91 items is used in clinical settings by a professional who has learned to administer the PDDAS (professionals can request free copies of the PDDAS and PDDAS-SV to the first author).

Diagnostic algorithm

Based on lifetime ratings, the PDDAS diagnoses AD and AS in persons by counting the number of major items as determined in DSM-IV. AD is diagnosed if the total number of major items rated D is ≥6, including at least two in area 1 and one each in areas 2 and 3; some developmental abnormality before age 3 in section XI exists; and no other PDD subtype better explains the condition (AD criterion C).

AS is diagnosed if two or more major items in area 1 are rated D; both AS screening item 1 (use of a meaningful single word before age 2 and meaningful phrase before age 3) and item 2 (intelligence quotient/developmental quotient [IQ/DQ]≥70 or estimated so) are met; at least one major item in area 3 is rated D; and no other PDD subtype or schizophrenia better explains the condition, without counting results of area 2 rating to AS diagnosis.

Because PDD not otherwise specified (PDDNOS) has no diagnostic criteria in DSM-IV, we devised PDDAS diagnostic criteria for PDDNOS as follows: at least one major item is rated D in one area and at least one major item is rated S in each of the other two areas, provided if no major item is rated D in area 1, either (a) or (d) in area 1 should be rated S (in this respect (b) and (c) are not used because (b) is not rated in children with developmental age under 3 and (c) was less discriminative than (a) and (d) between PDD and non-PDD in our clinical experiences) and no other PDD subtype or non-PDD disorder better explains the condition. These criteria correspond to ICD-10 criteria for atypical autism (AA) with atypicality in symptomatology. Because AA with atypicality in age at onset, AA with atypicality in both in onset and symptomatology and other ill-defined PDD subtypes in ICD-10 were virtually non-existent in our clinical experience, we consider these PDDNOS criteria to be the minimum PDD criteria.

If PDD symptoms that once satisfied diagnostic criteria for a PDD subtype are judged not to satisfy them later, partial remission is added to the diagnosis at that time.

The aforementioned process is depicted as the diagnostic algorithm in section XIV (not presented in this paper).

Participants

The participants were mothers of 77 PDD children (15 AD, 58 PDDNOS, three AS, one Rett's disorder; mean age, 4.6 ± 2.2 years, range, 2.0–11.0 years) and 64 non-PDD children (21 attention-deficit–hyperactivity disorder, three mental retardation, 11 borderline intellectual functioning, 11 communication disorders, four selective mutism, four other psychiatric disorders and 10 without any DSM-IV Axis I or II disorder; mean age, 5.2 ± 2.0 years, range, 2.3–10.7 years) who had visited the Nerima Welfare Center for Handicapped Persons from 1 December 2005 to 31 May 2007. The mean age did not differ significantly between the PDD and non-PDD groups but the IQ/DQ was significantly lower in 76 IQ/DQ-measured PDD children (mean, 76.7 ± 26.8) than in 62 IQ/DQ-measured non-PDD children (mean, 93.8 ± 20.6; t(136) = 4.11, P < 0.001). All of the mothers gave written informed consent to participate in the study, which was approved by the ethics committee of the Tokyo University Graduate School of Medicine in 2005.

Procedure

In the examination room were present the child with a possible developmental disorder, along with his/her mother frequently together with father, child psychologists to care for the child during the examination and the first and second authors. The first author interviewed the mother for approximately 1.5 h in order to conduct PDDAS evaluation of the child using the PDDAS-SV at the time of the first visit of the child to the center. The second author independently conducted similar PDDAS-SV evaluation by listening to the interview.

The diagnoses of the 141 children (77 PDD and 64 non-PDD) were made according to DSM-IV by consensus of experienced clinicians (third author and child psychologists) from all available information of the children (except for their PDDAS-SV data), such as detailed clinical records on developmental history, behavior and symptoms; the Childhood Autism Rating Scale–Tokyo version9 data; and observation records by nursery teachers who participated in remedial therapy groups in which almost all of the children were enrolled. After the completion of the consensus diagnoses, the second author, who did not participate in the consensus diagnoses, determined PDDAS diagnoses of the 141 children according to the PDDAS algorithm.

Statistical analysis

Based on PDDAS-SV data by the first and second authors, interrater reliability was examined (kappa coefficient, κ or Pearson's correlation coefficient, r) for the 36 items, 12 major items and three Asperger's disorder screening items in section XII and the 40 items in the other sections.

We tested discriminant validity of the PDDAS by comparing scores on the 36 items and the 12 major items of the second author's PDDAS-SV lifetime ratings between the PDD and non-PDD groups using the Mann–Whitney U-test. We similarly compared two groups of 38 PDD and 14 non-PDD children aged 2–3 not significantly different in IQ/DQ (mean, 75.2 vs. 88.6, P = 0.07) to examine whether or not results of the comparison between the whole groups would be sustained, because IQ/DQ that correlate negatively with the autistic symptom severity9 were not measured before age 4 in the other 89 participants.

To test concurrent validity of the PDDAS, we compared the agreement of diagnoses of PDD and its subtypes between the PDDAS and consensus DSM-IV diagnoses.

We analyzed data using SPSS version 13 (SPSS, Tokyo, Japan), with the significance level set at P < 0.01 (two-tailed test).

RESULTS

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

Interrater reliability

Table 1 shows that in sections I–XI, XIII, XV and XVI, values of κ in 25 items ranged from 0.81 to 1.00 (mean, 0.95 ± 0.06). In four items, in which κ was uncalculable, raw agreement rates between the two raters ranged from 0.91 to 1.00. Values of r were 1.0 in all of the other 11 items.

Table 2 shows that κ ranged from 0.69 to 0.99 (mean, 0.85 ± 0.08), 0.69–0.95 (mean, 0.86 ± 0.08) and 0.91–1.00 (mean, 0.97 ± 0.05) in the 36 items, 12 major items and three AS screening items, respectively.

Validity

As shown in Table 2, 33 of the 36 items and all of the 12 major items scored significantly higher in the PDD group than the non-PDD group, and three items (area/major item/item: 2/c/b, 2/d/c, 3/d/b) showed no significant difference (0.01 < P < 0.05). In the comparison between the two groups not significantly different in IQ/DQ before age 4, the PDD group scored significantly higher in major items (a) (c) and (d) in area 1; (c) and (d) in area 2; and (a) (b) and (c) in area 3, and non-significantly higher in the remaining four major items than the non-PDD group. The PDD group also scored significantly higher in six items in area 1, three items in area 2 and three items in area 3 and non-significantly higher in the remaining 24 items than the non-PDD group.

Regarding the diagnosis of PDD as a whole, the consensus DSM-IV diagnosis endorsed PDDAS diagnosis in all of the 77 subjects. Regarding PDD subtypes, the consensus DSM-IV diagnoses endorsed PDDAS dignoses in 14 of the 15 PDDAS AD subjects; all of the three PDDAS AS subjects and one PDDAS Rett's disorder subject; and 57 of the 58 PDDAS PDDNOS subjects. In two children the PDDAS diagnoses of AD and PDDNOS were consensus DSM-IV diagnoses of PDDNOS and AD, respectively.

DISCUSSION

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

The PDDAS showed satisfactory interrater reliability in the 36 items, 12 major items and three AS screening items in section XII and the 40 items in the other sections.

The 36 items seem to have content validity because they were created by experienced clinicians from the literature and their clinical experiences to well represent the DSM-IV AD criteria.2,8 The PDDAS also had satisfactory discriminant validity because 33 of the 36 items and 12 major items scored significantly higher in the PDD than the non-PDD groups. These results seem sustainable even if IQ/DQ difference is adjusted, although replication by a larger number of IQ/DQ-matched participants is needed.

In addition, the PDDAS had satisfactory concurrent validity because its PDD diagnosis agreed in all of the 77 children and its subtype diagnoses disagreed in only two children with the consensus DSM-IV diagnoses (i.e. AD and PDDNOS by PDDAS were PDDNOS and AD by DSM-IV, respectively).

Based on severity rating of the 36 items, the PDDAS uses the number of major items meeting DSM-IV AD diagnostic items in criterion A in full and at subthreshold in the three areas to diagnose PDD subtypes, instead of cut-offs as used in the ADI3/ADI-R.4 This PDDAS methodology is more straightforward than that of the ADI/ADI-R in judging how a subject satisfies diagnostic criteria for AD and other PDD subtypes, although a comparison between the two methodologies is necessary.

Some limitations of the present study need discussion. Because the present study was conducted in one clinic by professionals who closely cooperated, such a situation might have boosted otherwise lower interrater reliability and validity of the PDDAS. In this respect, studies by other research groups using not only the same methodology but also another methodology such as rating video-taped interviews by independent raters, are required to test the psychometric properties of the PDDAS further. Studies are also needed to test the PDDAS reliability and validity in subjects under age 2 and those over age 11 and in childhood disintegrative disorder, Rett's disorder and AS, the number of subjects for which were small in the present study.

In conclusion, the PDDAS, which takes approximately 1.5 h to administer, had satisfactory reliability and validity for diagnosing AD, PDDNOS and PDD as a whole despite some limitations to be addressed in further studies.

ACKNOWLEDGMENTS

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

We thank Ms Tomoko Nakano and Ms Mika Tobari for their assistance in data collection.

REFERENCES

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix
  • 1
    World Health Organization. The ICD-10 Classification of Mental and Behavioural Disorders: Diagnostic Criteria for Research. World Health Organization, Geneva, 1993.
  • 2
    American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 4th edn. American Psychiatric Association, Washington, DC, 1994.
  • 3
    Le Couteur A, Rutter M, Lord C et al. Autism Diagnostic Interview: A standardized investigator-based instrument. J. Autism Dev. Disord. 1989; 19: 363387.
  • 4
    Lord C, Rutter M, Le Couteur A. Autism Diagnostic Interview-Revised: A revised version of a diagnostic interview for caregivers on individuals with possible pervasive developmental disorders. J. Autism Dev. Disord. 1994; 24: 659685.
  • 5
    Lord C, Storoschuk S, Rutter M et al. Using the ADI-R to diagnose autism in preschool children. Infant Ment. Health J. 1993; 14: 234252.
  • 6
    Baird G, Simonoff E, Pickles A et al. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: The Special Needs and Autism Project (SNAP). Lancet 2006; 368: 210215.
  • 7
    Kurita H. Infantile autism with speech loss before the age of thirty months. J. Am. Acad. Child Psychiatry 1985; 24: 191196.
  • 8
    American Psychiatric Association. Desk Reference to the Diagnostic Criteria from DSM-IV. American Psychiatric Association, Washington, DC, 1994 (Takahashi S, Ono Y, Someya T, Trans. DSM-IV Classification and Diagnostic Manual of Mental Disorders. Igaku-Shoin, Tokyo, 1995) (in Japanese).
  • 9
    Kurita H, Miyake Y, Katsuno K. Reliability and validity of the Childhood Autism Rating Scale–Tokyo Version (CARS-TV). J. Autism Dev. Disord. 1989; 19: 389396.

Appendix

  1. Top of page
  2. Abstract
  3. METHODS
  4. RESULTS
  5. DISCUSSION
  6. ACKNOWLEDGMENTS
  7. REFERENCES
  8. Appendix

APPENDIX I

Item (a) of major item (a) in area 1 in section XII of Pervasive Developmental Disorders Assessment System

Item (a): Lack of eye contact (not exclusively when the child is scolded or feels nervous)
Objective of rating: To rate the degree of child's lack of eye contact with mother or others in lifetime (i.e. when it was most prominent before age 4) and at present.
Lifetime rating (method of questioning):
Remember situations where you were playing with him/her well but not where you were scolding him/her or he/she felt nervous, because it is natural for a child to avoid eye contact in such an instance. By age 4/Up to now (if under age 4), had your child shown a lack of eye contact definitely; or somewhat (namely, he/she had eye contact with you to some extent but had no eye contact with others, or had eye contact sometimes, or had eye contact only when he/she had a request to you); or never?
(‘Short duration of eye contact’ should be rated 0 because it is frequently seen in children with attention-deficit–hyperactivity disorder.)
Grade (circle the most appropriate one):
0. Not applied: Never (had good eye contact)
1. Slightly applied: Somewhat (i.e. had eye contact to a certain extent with mother but had none with others; sometimes had eye contact; or had eye contact only when he/she had a request).
2. Definitely applied: Had no eye contact even with mother.
x. Unratable (e.g. due to visual impairment).
Present rating (method of questioning):
How about now? Does he/she have a lack of eye contact definitely or somewhat or never?
Grade (circle the most appropriate one):
0. Not applied: Never (has good eye contact)
1. Slightly applied: Somewhat (i.e. has eye contact to a certain extent with mother but has none with others; sometimes has eye contact; or has eye contact only when he/she has a request).
2. Definitely applied: Has no eye contact even with mother.
x. Unratable (e.g. due to visual impairment).